Treatment of ulcer and nonulcer interstitial cystitis with sodium pentosanpolysulfate: a multicenter trial.

The effect of sodium pentosanpolysulfate (Elmiron) in the treatment of interstitial cystitis was observed in an open controlled multicenter trial. We studied 87 patients with symptoms for more than 2 years at 17 centers in Finland and Sweden. Patient selection was based on the typical chronic symptomatology but the material subsequently was stratified according to objective cystoscopic findings. The medication (400 mg. daily in 2 oral doses) was discontinued after 6 months. The response was evaluated every 4 weeks during treatment and every 3 months thereafter. Most patients responded favorably, many with diminution of pain within only 4 weeks from the start of treatment. The frequency of micturition decreased significantly and the mean volume per void per 24 hours increased in the patients without bladder ulceration but such changes were not found in the patients with ulcer. The bladder capacity was smaller in the ulcer group. In these patients the pre-treatment intensity of pain was somewhat greater than in those without bladder ulcer but the pain was alleviated in both groups and this effect was stable at the 3-month followup. The differences in responses in the 2 groups indicate a probable fundamental difference between ulcerative and nonulcerative interstitial cystitis. Side effects of the drug were few, slight and transient. Therefore, the study indicates that a significant number of patients with interstitial cystitis can be expected to benefit from treatment with sodium pentosanpolysulfate.